It is important to be aware of and understand the water resistance level of your watch. Unless your watch is specifically rated as water resistant, it should be shielded from all sources of moisture including excessive perspiration.
On the other hand, if the watch is rated water resistant, the number mentioned will indicate to what depth it can be lowered to.
Regardless of the rating, always try and avoid rapid change in pressure as your watch needs a little time to adjust. Never submerge your watch to hot water or take hot baths wearing it. This will lead to rubber seals contraction and water may leak in.
Always check your screw down crown and buttons to be tight closed before enter into the water. General it’s good to avoid water contact and when it happens then you much clean your watch with tap water and dry it with soft cloth, so all salt or chemical remains (from soap or shower gel) are removed. Salt and chemicals lead to seals corrosion and reduce their sealing ability.